• TI Thinks Resolved

DLPC3430: I2C Pulling Down on Power-up

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Part Number: DLPC3430

On initial power-up, we apply VSYS (3.8V) and then VCC (1.8V).  Before PROJ_ON pin is toggled, i noticed that the I2C0_SCL and I2C_SDA pins are pulled low.  These pins stay in this state until PROJ_ON turns on the DLPA2000.   After that, the I2C lines go High-Z.    After that, we can clear PROJ_ON and the SDA and SCL lines remain High-Z.

Is this behavior expected?  It seems strange that the I2C bus does not power up to High-Z by default.